bicycle generator permanent magnetism rated voltage: 12/24V DC raed current: 20/10A power: 350w The generator is generate three-phase alternating current , and output DC by rectification. The voltage range is from 0V to 30V, and it can be used to charge the battery. it is permanent magnetism .unfold size:1110*200*860MMpackage size:1030*285*860MM exercise bicycle use moto generator